Check valve credibility?

[blissville maples]

so, being a completely "by logic and common sense" type person, I have been listening to the check valve debate over the past years. I think its nearly impossible to compare anything in this industry since every year is drastically different, every tree can be drastically different, and every locations topography is different (big factor overlooked in topography is ground moisture), even if its only down the road. So we all or most of us have had these pesky ice jams in our y's, star intersections or another restriction in line that prohibits vacuum from getting by. I have seen 24'' on one side of an ice jam and it cant even pull vacuum through let alone sap. one big point to the check valve is that during freeze at night there is no draw back to tree due to the vacuum in the trees uptake process. it seems to me that if 24'' cannot move sap through ice blockage, how can 10'' (which is what studies show a tree can produce during uptake) furthermore I know I usually keep vac unit on until I see ice in releaser, if theres ice in releaser has to be ice in drop, in laterals, and in taphole. and if theres not there certainly will be very shortly. would it make sense to assume that there can be no draw back through any kind of tap weather check valve or not due to ice at T?? I really cant see how they have proof that a check valve was the reason they got more sap. a good healthy perfect vane of a tree can be a sap pump, if you lucked out and put a check valve in these areas, would make for a great result wouldn't it! I don't know just things you think about on way to work!!

[spud]

Anytime sap goes back into the tap hole it speeds up the healing of the tap hole. CV2 spouts will not allow that sap back into the taphole. Because of this the tap holes using CV2 spouts will outlast all other spouts on the market. The big question is (By how much)? Two years ago I used all CV2 spouts and got more sap per tap then any of my sugaring friends ( in my area). I am not saying I got more sap then everyone. I still remember posting my sap amounts each day with a bunch of fellow Traders. It's always fun to see what everyone else is doing for gallons on a daily bases. There was one person that would question my amounts a lot of times because others were not getting anything. The lay of the land and the location of your woods has much to do with sap flow. There were days I was shipping 6-8000 gallons and my neighbor got near nothing. He even waved down the sap truck one day just to ask if I was really getting sap. I know for sure that the CV2 spouts were allowing me to get higher volumes of sap per tap then others around me. If you look at the PMRC production for the last 10 years it should tell a person the CV2 spouts really do the job. The other great thing about the CV2 spout is they grip the tap hole so good that you will never have to re seat them mid way through the season.

Spud

[GeneralStark]

Yep they work. Not as well as a new drop and spout but pretty close.

[DrTimPerkins]

Yep they work. Not as well as a new drop and spout but pretty close.

That is correct, but the real question (for most producers) is which approach produces the highest net profit (increased income from higher sap yield minus costs to implement the strategy).

There are three main places that have done SCIENTIFIC RESEARCH on the CV spout. Now I've written before about the great lengths that real scientific researchers go to in order to limit the variables and sources of variability you mention. That is what we train to do....design and conduct experiments that test the thing we actually want to test. Yes, doing research in the woods makes it more challenging, but one way you get around that is to includes LOTS of replication, so little things like that tend to get factored out.

Centre Acer (Quebec) did two studies. The first had some problems and can be ignored. The second study was done in two sites. The results from that work from a translation of the abstract are: The results obtained showed that the replacement of the spout by a new health check-valve spout allowed to significantly increase the yield of the two sugar bushes in the study.

Cornell University. Steve Childs has done NUMEROUS studies looking at various sanitation approaches, including the CV Adapter and CV spout. You can ask him yourself, but a quote he made several years ago was: …the check valve, which performs very well, is probably the most cost effective choice.

UVM PMRC. We have done dozens of studies comparing the CV adapter and CV spout to other approaches. The results are pretty clear. I don't need to recount them here....feel free to look for the publications on our website http://www.uvm.edu/~pmrc The CV approach, while not always producing the highest sap yields (as the General said, and as Steve Childs has said, and as I have said that is typically achieved with a new spout and drop, but that is costly and thus doesn't produce the highest net profits) is generally a close 2nd in terms of yield, but is generally first in terms of net profit.

We (Cornell/Steve Childs and UVM PMRC/Perkins and van den Berg) finished a 2 yr study in 2015 coming chemical sanitation, replacement (new spouts, CV, new drops), and cleaning+replacement. Over a total of 6 studies in those two years in two sites, the CV spout consistently produced the highest net profits. Although the plan was to stop with the research after 2015, we're going to repeat it again at PMRC in hopes that we get a different type of season (2014 and 2015 were both very similar). Regardless of that, it's unlikely the story will change very much. We'll be coming out with several products (papers, videos, spreadsheet tools) over the next year to help people make their own management decisions for their operations.

In summary, the SCIENTIFIC studies from each of the major places doing sap production research have proven that the CV approach to sanitation works.

I've personally heard from hundreds of producers who've used them and thought they helped. That's great. I've certainly heard from some who didn't like them. That's fine too. Nobody is forcing you to use them.

The proof is in the pudding. The average UVM PMRC production over the past 11 yrs is 0.59 gal syrup/tap (or 6.5 lbs/tap). It would actually be higher except that we often use 50% or more NON-CV spouts in some parts of our woods to allow comparisons. Doing that drags our production yields down somewhat. If we didn't have to do that, I'd have a CV spout in every taphole here unless we had put new drops in. Using the CV we don't normally change drops unless the fittings are starting to come off the tubing. Our 10-11 yr old tubing last year with CV spouts produced as much tubing that was only a few years old with CV spouts.

[blissville maples]

as I said how is sap going back into taphole when t is frozen?? if 24'' cant move it then how can 10''?? I had a bush on gravity, well 10-15'' natural vac with over 100 feet of drop mountain goat country in Middletown springs. on good run day, 250 taps into container (site has 3 containers for 425 taps pain in butt) easily see 350-400 gals on a good run, 150-200 end of season no freeze run. total taps at this bush 425, last year sap total around 4300 gals. no cv's don't know if could get much better on gravity and nat. vac..........spud, prior to two years ago what spouts did you use?? what was your total sap yield per year then versus now. if you had reg spouts for ten years on say 1000 taps and got say bad year 10k gals sap lo and good year 15k hi. if you swapped for cvs and did another ten years and say went from a bad year of 13k to a best year of 18-20k id certainly agree that cvs my have some influence. can be tough comparing with neighbors, tap hole depth, lines, technique, many many things, way too many things to accurately say. and then of course vacuum multiplies these variables b/c none knows what vacuum level every one of their trees is receiving(good setup all trees on laterals get 27'' bad setup first 2 trees on laeral get 27'' next 2 are 24'' and the last 2 to 3 are say 16'' due to losses), nor do we know how much production we lose to these leaks plugs etc, which would throw off any accurate comparison. I just set up 1000 taps. 550 leader cv's, 450 white smart spout. all trees are insight of eachother, all will have 27'' and all have both east west exposure (couldn't ask for better). of 550 cv trees 450 of them have crowns extending down 2/3 the tree and all are 14'' plus, with maybe 5 ugly culled trees. next to hay field. the 450 smarts id say 100 14'' + trees with extended crowns. most are less than 14'' of those, 60-80 taps will be in trees less than 6'' (need thinning anyways) and will be using 5/32 adapters drilling 1/2'' hole. if the cvs don't blow the others out of the water by volume and longevity we have some problems. im very interested to see how this plays out, however im skeptical of these cv's, especially when im thinkin ice jam in the t has to be preventing the backflow in a regular spout anyways. we'll see, thanks for reply

[blissville maples]

it would be interesting, like I said a ten year to ten year comparison, two years is somewhat short. and the pmrc has 11 year avg of .59. but that figures cvs coming out in 09? or 10?, so the first 3-4 years were reg spouts only correct?? don't get me wrong the concept of no microbal contaminated sap back to taphole is there but I think ice jam in t, taphole, or loop in drop would produce somewhat same effect. all is interesting

[BlueberryHill]

I read all this sciency stuff about the earth going around the sun. But I still think that the earth is the center of the universe and the sun is going around us. I stand out here in the field and I can tell you for certain that I am not moving at all. The sun and moon are the ones moving. I stood there all day yesterday just to make sure. I swear I never moved once. I enjoy the debate, but I'll need some solid evidence before those academics convince me of anything.

[BreezyHill]

Cornell University. Steve Childs has done NUMEROUS studies looking at various sanitation approaches, including the CV Adapter and CV spout. You can ask him yourself, but a quote he made several years ago was: …the check valve, which performs very well, is probably the most cost effective choice.



Was this quote prior to the results of recent sanitation studies?

Thanks
Ben

[DrTimPerkins]

Was this quote prior to the results of recent sanitation studies?

The quote was from a few years ago. However the results of the study you refer to, in my opinion, only serve to confirm those words.

I shared the graph below earlier in a different thread. It is a summary from that study showing net profits for each strategy above the cost of doing nothing (old spouts on old drops). I think the results are consistent with my statements and with the quote I used. I'm not going to engage in a long discussion of all the details, as we are working on the outputs of that work now for publication.

12457

[maple flats]

Let me guess, There is a time, as the temperatures drop that the sap has not fully frozen at the interface between the tap hole and the drop, but the flow is not moving because the lateral lines have frozen. With greater mass at the tap hole the sap can still be pulled back into the tree. The CV stops the back flow into the taphole.
I see a great advantage in the length of time a tap hole stays wet. Last year we tapped late because of snow depth, but we tapped mid March, got sap thru Apr 19. Then I did some Blueberry work and returned to pull taps in early May, finishing May 11. By far most (but not all) were still running on that last day, in fact over 90%.
The year before we were tapped by Jan. 20, because my college help returned to school Jan 21. The sap did not run until the last week in March (another late start). We hauled our last sap on Apr 17. Again, I then went to do work in the blueberries. That year I finished pulling taps on May 16 and I again had 90%+ that were still running. I never had anything near that before I started using the CV's, 1st the CV1 (adapter) and now the CV2 (tap spout). My tap pull dates have always run from early may thru about the 3rd week in may. I used to have at best about 5-10% still wet at that date without the benefit of he CV.

[blissville maples]

if the taphole interface is not frozen, there is no vaccumm within the tree, there cant be not cold enough at that point. so without the presence of freeze within the tree there will be no draw back to taphole

[blissville maples]

I don't know about actual running drip drip taps in may, perhaps the tapholes were moist/wet, and ive seen this without cvs. ive watched reddish brown sap drip out in may- u wanna taste buddy sap- wow anyways it just seems to me that there is a lot of talk about taps running later but I don't hear of folks going from .35 to .5 gals per tap to .6 or .75 so.......if were getting so much more sap how come were not seeing more >.6 per tap outputs, should all go hand in hand. also just cause tapholes are moist doesn't constitute a run of sap and without that there is no gain. I will be certainly paying close attention this year as will be employing them in some of my own experiments. cant say ive seen too many trees stop leaking from not using cvs usually is the lack of cold weather

[maple flats]

I'm not saying I was still collecting the sap, it surely would be buddy, but the tap holes were more than just wet, as the taps were pulled I had a small steam run down from the hole, not as much as you get when you tap and the sap is flowing but non the less a streak formed and it often runs all the way to the ground as we look a while later.
However, you have the right to use any tap you choose. You can make less syrup if that is your goal.

[blissville maples]

last year, spouts 3 years old, ive never changed until this year, after having many days of 45-50 degree weather, I was getting 80 gals sap out of 450 trees. out of 1700 trees I was collecting 400 gals- really shutting down end of season everyone is trying to filter ropy comm. etc. so I was done not making much so I went to pull, I wanna say this was 3rd week of april. like u said sap hitting the ground, im like wait a minute and almost stopped, but I knew better id waited the previous week for a tank of sap. there is always sap at the taphole when there is temp change. even in may u see a 35 degree night and a 55 degree day, tapholes will be wet. until the trees start their seasonal growth ive seen this. as ive said ive seen reddish brown dripping out of tree, doesn't mean you can make syrup, takes volume. not trying to be a killer of someones efforts however we're in a commercially, financially driven world, if you haven't noticed sugaring stiuff is about 100% overpriced (nothing you can do like gas) no reason a releaser rubber flapper should be 50 bux, so figure in money and sometimes have to stop and think. time tells all, and time will sooner or later debunk or verify these cvs. like I said when we start seeing folks making .75 per tap regularly when they were at .5 prior because they are making syrup in july, then we can talk, however a wet hole in april doesn't constitute much to me, other then wet taphole which doesn't require a cv. so taphole may be wet b/c a few vains aren't totally plugged, the other 99% are and no sap tanks are running over so........good chat, ill be sure to post volumes with cvsand volumes with non cv on both new bushs this year as well as the current bushes, maybe ill see .75 per tap!! good luck

[GeneralStark]

Pretty hard to follow your random train of thought posts but are you saying you put up a bunch of new tubing and are going to use CV spouts on new tubing?

If you really want to debate the credibility of the CV spout you are pretty late to the party. I would encourage you, especially as you are new here, to discover the "Search" function so you can check out existing threads on the subject. There are lots....

[spud]

I don't know about actual running drip drip taps in may, perhaps the tapholes were moist/wet, and ive seen this without cvs. ive watched reddish brown sap drip out in may- u wanna taste buddy sap- wow anyways it just seems to me that there is a lot of talk about taps running later but I don't hear of folks going from .35 to .5 gals per tap to .6 or .75 so.......if were getting so much more sap how come were not seeing more >.6 per tap outputs, should all go hand in hand.

I hear of sugar makers getting .5-.6 often. There are several on Trader. Most of these people use the CV2 spouts. The problem is most people think their smarter then the people doing the research. Their lack of understanding causes them to keep doing things their way instead of doing things the right way. A well known researcher told me a few years ago that their are sugar makers and their are people that just tap trees. Their ignorance is causing them to do less then what they could be doing. I talked to a guy a few years back and he said his best friend switched from smart spouts to CV2 spouts. His friend had been getting .3-.4 GPT each year using the smart spouts. He has been using CV2 spouts since they came out and his production now is .5-.6 and his drops are much older. So I asked the guy if he now is also using the CV2 spouts? He said no he is happy using the smart spouts and getting .3 GPT. If a stupid sign was close by I would have stuck it to his forehead.


also just cause tapholes are moist doesn't constitute a run of sap and without that there is no gain. I will be certainly paying close attention this year as will be employing them in some of my own experiments. cant say ive seen too many trees stop leaking from not using cvs usually is the lack of cold weather


Most all tap holes will be wet when you pull your spouts. This does not mean your tap holes were still productive till the end. Using the CV2 spouts will allow less bacteria to form in the taphole causing the tap hole to be far more productive throughout the season. The name of the game in sugaring is not how many taps you have or how big your sugar house may be. It's not about all the new shinny equipment you have either. People can have all of that nonsense and impress their friends but if they are only getting .25-.35 GPT then there is something wrong. If a person wants to be the best he can be in sugaring then he needs to take advise from people that consistently get high GPT. PMRC and Cornell provide FREE research information to all those that want to learn to be a real sugar maker. I would love to get the GPT amounts that PMRC gets. I am doing everything I can to reach those numbers. I am not in a position to question the researcher like Dr.Tim because he is far better at this game then I. Although there is nothing wrong with asking a bunch of questions even if they seem silly. He will answer for free.:)

Spud

[WESTMAPLES]

generalstark, spud, and dr tim are right!!! do your own search about CV topic we have all been involved with for the past few seasons, listen and follow others that are looking at the glass as half full...... dr tim has done the time, and put forth the effort to inform, educate, and answer our questions about maple everything. one of my close maple friends and maple educater jeff mason owner/ operator of the red bucket passed away recently he always said `listen to others with both ears open you will always learn something new `.......

[Tigermaple]

You're problem check valves seems to be the tree not overcoming frozen sap up in the lines. You're right I don't see how frozen sap could be sucked back up into the tree. But of course there's many times when it is sunny out and well below freezing the sap thaws in the lines due to the greenhouse effect but the tree doesn't give a drop. This is when a check valve or a new drop would be most effective (or when the vac craps out). I look at check valves as a cost saver because you don't have to replace your drops as often. Research seems to show new drops beat everything at production but check vales are the most cost effective. That said it would be nicer if they were cheaper.

[blissville maples]

spud, I agree, many people are tappers not sugarers. u may believe I am one of them, by my posts. I can assure you that im not. believe me of this, im addicted to knowledge and doubt too many peole learn as quickly as I do, i believe many people don't use enough common sense or think with DYNAMICS meaning from different angles not just the obvious they are called simple people for instance- I keep hearing about laterals thawed out on a 30 degree sunny day, ok maybe so(in the sun) however that tree is in sun as well especially the tops and those tops in the sun WILL create pressure not vacuum the trunk is in sun also and is dark in color that will attract heat on half the tree so with this and temps hovering 30 I dunno don't have me convinced yet.......is that common sense or what??.....if there Is ice turning to liquid there is not ENOUGH cold to create enough vacuum to pull back sap. now with vac pump and single releaser you can get kick back-that will introduce sap back to hole and a CV WOULD prevent this. but uptake at night- that's a complete joke, maybe this will make me look not so biased. as far as researchers- be careful with them-you cannot believe everything you hear, matter of fact most you hear is wrong. take a look at all the common human error involved in studies, hard to rely on people these days. and im not sayng dr tim isn't worthy of his credentials by any means. im a skeptical person, everyone else should be as well. money wins every time, many studies involve money. im all about logic and practicality, has made me a very successful person. you have finally showed me someone who has made a gain by going with cvs, some proof. now lets see if that continues for longer than 3 or 4 consecutive seasons. time tells all/everything and anything you wanna know always has always will, a brief period does not.
lunchbreak over time to get back in woods not liking this wet weather, snow would be better already soaked to the arse!

[blissville maples]

I have used cv and will this year, sooner or later it will be bam- yes they make a big difference or it will be ok they help some but not as initially thought. as I said theres really no way to compare year to year tree ot tree its like trying to guess which way the wind will blow at 3am on sunday, pretty hard to even say at all in my opinion. I think the debate will always be there b/c some bushs will propser with cvs and some may not- this again comes down to topography and ones own dedicated experiences with them

[palmer4th]

So I settled on using clean seasonal spouts the last couple years because I did not understand the research I had read about check valves. I remember reading that the best results happened when check valve taps were used in conjuction with new drops. If u have to replace the drop then how is the check valve working?

[spud]

So I settled on using clean seasonal spouts the last couple years because I did not understand the research I had read about check valves. I remember reading that the best results happened when check valve taps were used in conjuction with new drops. If u have to replace the drop then how is the check valve working?

You don't change the drop if you're using CV2 spouts. PMRC has 10 year old drops and still gets .5 or better all because of the CV2 spouts. If you had 10 year old drops and used any other spout you would not come close to a .5 GPT. CV2 spouts should be used on the third year of you're drops and beyond. To replace a drop it cost about .50 cents and it requires a lot of man hours. A CV2 spout cost .36 cents and there is no additional work involved. As long as my production is close to the same as new tubing then I will continue to use them.

blissville maples- I tend to question lots of research that is being done in all fields. I would never think of you as being dumb for questioning research so please don't think that. For this season I have split my woods in half. I run two pumps that run 28.5 inches in the sugar house. I have two releasers dumping into different tanks. I chart all my sap and I know what section does better and by how much. About half my woods will have CV2 spouts on 5 year old drops. The other half will have 3000 taps using white CDL Max Flow spouts along with 1500 or so CV2 spouts. The CV2 spouts in this section will be on 4 year old drops and the Max Flow spouts will be on 2 year old drops. I plan to compare the two sections and see which one out preforms. All 9000 of my taps are in one woods right in my backyard. There is an elevation difference of about 400 feet. I will share my numbers throughout the season if you are interested.

Spud

[maple flats]

I don't use the check valves on first yr. drops, just 2nd year and beyond. I however try not to have any drops over 6 yrs old, most are 5 or less.

[WESTVIRGINIAMAPLER]

One thing to remember is Proctor only puts in one tap per tree regardless of size of tree unless that has recently changed which will of course give more gpt.

[madmapler]

This may be the topic of a new thread but I just did some calculations based on what I pay for cv2s($.40 typically) and what I pay for clear spouts ($.16 typically) and what I pay for semi rigid tubing($50. per 500ft. roll) I admit that the roll price is a good one and that its been established because I've bought an abundance and that the spout prices can be better when discounts apply. According to my figures, a new 32" drop and clear spout comes to 48 cents per tap. It can be argued that if you cut your drops at the tree as I do then a drop needn't be 32" at every tree especially when changing them yearly. The price per tap would then most likely drop below the cv2 price. I wonder also about possibly changing a section of the drop yearly say 10 or 15". Would this be sufficient to serve as a new drop if done yearly? If so then we're looking at a cost that may be quite a bit less than a cv2 and that performs better. It may not be for everyone but would certainly be beneficial for many.

[ennismaple]

Blissville - Sounds like your sugar bush is quite hilly so maybe CV's are not as effective for you? We have a lot of sections of mainline that are 0.5% slope and laterals that are dead flat. The CV's work great for us to keep sap from being drawn back into the taphole. The first season we used them we got more sap during the last week of the season from a 400 tap section of the woods (using CV's) than we did from a 1400 tap section that was immediately adjacent (not using CV's). We were making a good amber not commercial mersh so it was definitely worth it for us.

[DrTimPerkins]

One thing to remember is Proctor only puts in one tap per tree regardless of size of tree unless that has recently changed which will of course give more gpt.

Although this comment is somewhat immaterial to the conversation, you are correct in that we use only 1 tap per tree. However it is not done, as many people seem to assume, to inflate our production numbers, but rather because our very old trees were heavily overtapped for 60 years with multiple taps per tree (and some of them had been tapped using PFA tablets back when that was legal), with fairly short droplines, and with 7/16" spouts. In some areas we were hitting stained wood 13% of the time (we examine shavings from almost every hole we drill to keep track of this). Anytime you hit an old stained area you get very poor production from those trees. In those areas, it is exceedingly hard to find good fresh wood to tap into. If we were putting two taps in those trees the probability of hitting old stained areas would continue to increase, thus something had to be done to correct the situation.

We switched to 5/16" spouts, put in long-droplines, and only one tap per tree to let the trees have a break and time to regrow new fresh wood. We also went to shallower tapholes, only 1.5" deep, which result in lower production. If you've been to our site, you would also realize that given that we are at 1,400' elevation on the side of the windiest mountain in the whole state, our trees are already under fairly high stress. We actually tried to switch to two tapholes for the larger trees and to 2" deep tapholes a couple of years ago, but were still running into the problem of hitting stained wood, so we backed off again and went back to only 1 tap per tree and 1.5" deep tapholes for a while longer.

If we wanted to truly maximize production even higher just to look good, we'd go with deeper tapholes and drop out the real large trees where we hit stained wood frequently.

[DrTimPerkins]

According to my figures, a new 32" drop and clear spout comes to 48 cents per tap.

Two things. This does not include the cost of a new tee. Many or most people who replace drops will cut out the tee because it is much faster to do it that way. Secondly, you don't include the time (which is a cost) of making the drop, or the time (again a cost) for deploying them in the woods.

As for the length of drop needed to influence sanitation at the taphole.....it depends greatly upon the system, how it is operated, and what type of backflow conditions occur in your operation. In most cases, the people we've spoken with like to minimize the number of fittings (potential leak points) in their system, so having an extra union in the middle of the dropline isn't something most people desire.

[DrTimPerkins]

So I settled on using clean seasonal spouts the last couple years because I did not understand the research I had read about check valves. I remember reading that the best results happened when check valve taps were used in conjuction with new drops. If u have to replace the drop then how is the check valve working?

It is not recommended that you use CV spouts or adapters with new drops. The benefit would be very marginal. In general, the older the droplines, the higher the level of benefit gained by using CV (or by using any NEW spout...although the CV provides added benefit beyond JUST a new spout).

[madmapler]

Two things. This does not include the cost of a new tee. Many or most people who replace drops will cut out the tee because it is much faster to do it that way. Secondly, you don't include the time (which is a cost) of making the drop, or the time (again a cost) for deploying them in the woods.

As for the length of drop needed to influence sanitation at the taphole.....it depends greatly upon the system, how it is operated, and what type of backflow conditions occur in your operation. In most cases, the people we've spoken with like to minimize the number of fittings (potential leak points) in their system, so having an extra union in the middle of the dropline isn't something most people desire.

I was just considering the thought for those who might think the time to be worth it. I can certainly see why a large operation wouldn't do it but I don't think I'd mind making up drops in my down time as I know some others do. I personally would reuse the tee. Using semirigid exclusively, I don't find any leaks around my fittings unless its been otherwise damaged but I'm still relatively new and my tubing is only a few years old. Thanks for responding. I was hoping you would.

[unc23win]

I wonder also about possibly changing a section of the drop yearly say 10 or 15". Would this be sufficient to serve as a new drop if done yearly?

I believe Theron made extensions for his drops with hook connectors. Also many companies are now selling pre drops with no fittings I think Lapierre 30" are like .18 each cheaper than if you by the roll (even on sale) and make them yourself.

[DrTimPerkins]

... I don't think I'd mind making up drops in my down time as I know some others do. I personally would reuse the tee. Using semirigid exclusively, I don't find any leaks around my fittings unless its been otherwise damaged...

That time you spend is worth something. You could be doing something else to make money if you weren't making drops, so either way, it is always considered a cost in ANY type of economic analysis.

As far as re-using the tee, I know that some people try. The issue is that as your vacuum gets really high, those fittings tend to have a higher probability of leaking, so you either spend time looking for those microleaks, or your vacuum suffers. We've found, and I think may others who get real high vacuum have as well, that cutting out the tee is the best approach due to the time savings and due to the microleaks issue. Otherwise you spend time and money going back and looking for those leaks, which costs you money in the long-run.

Jared mentioned pre-cut tubing for drops. Yes, that is a possibility, but you still have to spend the time putting on the fittings and bringing them out in the field and replacing them. I do agree though, that IF you can get the drop cost down really low (including the time required to make them and deploy them), that it would produce the highest sap yields and perhaps a good net return. That is really only a possibility for those who can get the cost (again, including time/labor) down really low and if they also get really high production (due to good trees, good sanitation, and good vacuum). I don't think we're at that point yet.

[blissville maples]

ennis, yes some have to pull yourself up!! nice at times- your slope scenario makes good sense. I also notice sloped runs the laterals seem to stay much cleaner- less darkening of mildew etc. which would probably mimick trees microbal level. so maybe this counteracts their use

Dr tim?
any idea if amount of microbe activity/ residue affect to any extent how well the tree heels or slow healing down? have some older trees 18'' + on 3 year old spouts, used larger 7/16ones which converting this year but they don't seem like they heal well- the first year anyways, second to third year holes look ok. would assume a bad spot in tree also would cause this, which some are probably iffy inside, maybe hollow in a couple

[blissville maples]

spud- yes would be good to hear your info, I have 3 different spouts this year very similar bushes, im going to pay very close attention this year. but I need to quit changing things in woods and adding few here and there, that has made a comparison hard for me

[DrTimPerkins]

any idea if amount of microbe activity/ residue affect to any extent how well the tree heels or slow healing down? have some older trees 18'' + on 3 year old spouts, used larger 7/16ones which converting this year but they don't seem like they heal well- the first year anyways, second to third year holes look ok. would assume a bad spot in tree also would cause this, which some are probably iffy inside, maybe hollow in a couple

By the end of the season there are plenty of microbes in the taphole to elicit the wound response. Closure of tapholes occurs via growth from the outer edges inward. It definitely takes longer for a 7/16" taphole to close. They'll probably close a lot better with 5/16" holes. Might be that you hit an area of the tree that wasn't doing real well due to high tapping intensity or some other stress though. Change over to 5/16" spouts on those trees and keep an eye on it.

[blissville maples]

does the hole grow together on the inside below the cambium layer?? it doesn't stay hollow does it? I started tapping here 4 years ago, I think got hit bad ice storm 98'. I know many have bad culls and some are hollow so hitting bad Area is very possible and kinda what im thinking. funny I was up there and one tree was dead on one side and there was around a dozen of those, I guess their called "ichneumon" wasp, daggers sticking out of tree. I knew what they were b/c ive seen a few of them and remember reaing about them, they hatch in trees!! freaky looking wasp!

while on subject of wounding, I have many 4-8 inch maples on edge of my meadow, im going to tap some using 5/32 adapters. im assuming a 1/2 or 3/4 inch hole would not hurt a tree this size. seems to me tapping smaller trees would not hurt them since they are so robust and would only drill in a proportionate distance relative to the diameter. whats your thoughts on this??

[DrTimPerkins]

does the hole grow together on the inside below the cambium layer?? it doesn't stay hollow does it?

These are different topics altogether, so I'll start a different thread over here.
http://mapletrader.com/community/showthread.php?26879-tree-growth-and-tapping-small-trees&p=290711#post290711

[mapleguy]

Heres my 2 cents on the cv taps, they are absolutely a necessity. I have 1000 taps with gravity and I wouldn't be without them. they make an unbelievable difference. don't out-think this